Examine source code of Best by Date

{
  "manifest_version": 3,
  "name": "Best by Date",
  "version": "1.10.3",
  "description": "Automatically close, discard, or deduplicate matching tabs after they have been inactive for a set amount of time.",
  "permissions": [
    "alarms",
    "menus",
    "sessions",
    "storage",
    "tabGroups",
    "tabs"
  ],
  "background": {
    "scripts": [
      "lib/rules.js",
      "background.js"
    ],
    "type": "classic"
  },
  "action": {
    "default_icon": {
      "16": "icons/best-by-date-16.png",
      "32": "icons/best-by-date-32.png",
      "48": "icons/best-by-date-48.png",
      "64": "icons/best-by-date-64.png"
    },
    "default_title": "Switch to the next audible tab"
  },
  "commands": {
    "switch-audible-tab": {
      "description": "Switch to the next audible tab"
    },
    "trigger-now": {
      "description": "Trigger every applicable Best by Date rule now"
    },
    "toggle-pause": {
      "description": "Pause or resume Best by Date"
    },
    "protect-current-tab": {
      "description": "Protect the current tab from Best by Date"
    },
    "undo-last-sweep": {
      "description": "Undo the last Best by Date sweep"
    }
  },
  "icons": {
    "16": "icons/best-by-date-16.png",
    "32": "icons/best-by-date-32.png",
    "48": "icons/best-by-date-48.png",
    "64": "icons/best-by-date-64.png",
    "96": "icons/best-by-date-96.png",
    "128": "icons/best-by-date-128.png"
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "best-by-date@local",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}